Joint for tubular members



Aug-A 1958 A. E. F. JOHNS ON JOINT FOR TUBULAR MEMBERS File d Oct. 30. 1952 INVENTOR.

BX fl w/M W ATTORNEYS.

' United States Patent '0 JOINT FOR TUBULAR MEMBERS Axel E. F. Johnson, Cincinnati, Ohio, assignor to American Hospital Supply Corporation, Evanston, Ill., a corporation of Illinois Application October 30, 1952, Serial No. 317,760 4 Claims. (Cl. 287-56) This invention relates to a joint for tubular members and a method of forming the same. The invention'is highly useful in connecting cylindrical metal parts or tubes in the fabrication of various types of structures and through the use of integral interlocking partson the joined members.

An object of the present invention is to provide a method and means for joining tubular members without employing welding or utilizing bonding materials. A further object is to provide an effective method for the union of tubular parts by utilizing integral portions on the two parts to provide the interlock therebetween. Yet another object is to provide a novel form of joint between tubular members in which the tubular members are interlocked rigidly through the use of integral elements on both members. Yet another object is to provide a method for joining tubular metal parts and the like, or parts having tubular portions, whereby one of the parts extends transversely through the other and is provided with raised portions enclosing the edge portions of the other member to form an interlock. Other specific objects and advantages will appear as the specification proceeds.

The invention is shown, in illustrative embodiments, by the accompanying drawing, in which- Figure 1 is a broken top plan view of tubular elements joined together in accordance with my invention; Fig. 2, is a vertical sectional view showing one tubular member provided with an opening and the end portion of another tubular member to be inserted therethrough; Fig. 3, a sectional view, the section being taken as indicated by the line 33 of Fig. 1; Fig. 4, a view similar to Fig. 1 but showing a modified form of the invention; Fig. 5, a sectional view showing a solid member having a tubular portion about to be introduced through a transverse opening in the other tubular member; Fig. 6, a sectional view, the section being taken as indicated at line 6-6 of Fig. 4; Fig. 7, a view similar to Fig. l but showing a further modified form of the invention; Fig. 8, an assembly view, partly in section, showing the parts of Fig. 7 prior to the forming of the joint; and Fig. 9, a broken sectional view, the section being taken as indicated at line 9-9 of Fig. 7.

In the illustration given in Figs. 1 to 3, inclusive, 10 designates a cylindrical member which ,is provided with a transverse opening 11 extending therethrough. Thus, in forming a transverse opening or passage through the tube 10, it is necessary to form two aligned openings 11, as illustrated more clearly in Fig. 2. A second cylindrical member 12 is passed through the transverse opening 11 and preferably the outside diameter of the member 12 is such as to cause it to fit fairly tightly the opening 11 within member 10. vA problem is presented in attempting to unite the two tubular members after they are thus arranged at right angles to each other with the tube 12 extending through the opening 11 of tube 10, because the edge of the metal around each opening 11 lies in a plurality of planes and, of course, such edge would not 2,846,249 Patented Aug. 5, 1958 terlock can be formed between the two members by press-- ing an expander tool such as a solid cylindrical wedge 13 having preferably a reduced forward end portion 14 through the tube 12, as indicated more clearly in Fig. 3, to expand the tube 12 and cause it to lock itself into the outer cylindrical member 10. The expander tool or solid cylindrical wedge 13 should be longer than the diameter of the outer tube 10 so as to expand the tube 12-against the outer faces of the outer tube 10, as shown more clearly in Fig. 3. In the operation described, I find that the tube 12 expands on either side of the metal edges.

15 about the opening 11 so as to form not annular grooves but grooves which extend in an arcuate plane along the exterior of tube 12 to receive the edges 15 of the outer tube 10. The resulting interlock is unusually strong by reason of the connection of the two parts along such arcuate lines.

In the modification shown in Figs. 4, 5 and 6, a solid bar 16 is provided at its end with a hollow or tubular portion 17, and the latter is passed through the opening 11 of tube 10 in the same manner as described above in connection with Figs. 1, 2 and 3. The expansion is similarly caused by passing the expander tool 13 through the hollow portion 17 of the bar 16 to interlock the parts as illustrated in Figs. 4 and 6.

In the embodiment illustrated in Figs. 7 to 9, inclusive, a cylindrical member 18 is provided with a downwardlyinclined end portion 19 terminating in a tubular portion 20 of substantially uniform diameter. The portion 20 is extended through the opening or openings 11 in the member 10 and then expanded therein by placing the expander tool 13 therein, as above described. In this structure, the inclined wall 19 is eifective in aligning the tubular members 12 and 18 and the inward movement of the expander bar 13 forms the beads on both sides of the edges of the metal about the opening 11 so as to firmly unite the members.

In each of the operations described, the expander tool not only causes the metal of the inner cylindrical member to flow outwardly about the edges of the outer cylindrical member to produce the groove, but also such action causes the flowing metal about such edges to bring about a firm and rigid interlock between the parts. Since the inner tubular member is extended beyond the edges of the outer tubular member and the expander tool is also passed through the inner tube beyond such edges, there is formed a bead structure of angular or arcuate shape on the inner tube and one each side of the edges about the openings 11. It is further found that this joint possesses unusual strength and rigidity.

While in the foregoing specification I have set forth specific structures in considerable detail for the purpose of illustrating embodiments of the invention, it will be understood that such details of structure may be varied widely by those skilled in the art without departing from the spirit of my invention.

I claim:

1. In a joint structure, a tubular member having a pair of aligned openings in opposite wall portions thereof, a shaft member having a hollow end portion extending through both of said openings and tightly engaging the opening defining edges of said tubular member, and said shaft having raised area s inside and outside of said tubular member adjacent said openings and substantially abutting the wall portions of said tubular member throughout the entire perimetric area thereof about said openings.

2. In a joint structure, a tubular member having a pair of transversely aligned openings in opposite wall portions thereof, a-shaft member having a hollow end portion extending: through both of said openingsand' projeetingoutwardly from saidtuhular member oneachside thereof, said shaft member tightly engaging the edges of said tubular member that define said openings, said shaft integrally formed raised; areas: inside and, outside 5 oliisaidtnbulanmember adjacent said openings. and substantially abutting: the. opposite wall portions; of said tin-.- hulan member throughout: the: entire. perimetric areas thereof about. lJQflLOfi said openings.

In a joint: structure: of the character: described, a; 6

cylindrical tubular member; having apair of diametrical- Iy' opposed openings extending. therethrough, a shaft mem-- her' having. a hollow end portion extending completely: through botlr of said openings and? projecting outwardly from said tubular member on each side thereof; the hol- 15 raised area inside of said tubular member and extending between. the opposite, wall. portions. thereof, all of said raised areas substantially abutting the wall portions of said tubular member throughout the entire perimetric areas thereof about the openings.

4. The structure of claim 3 in which said hollow end portion of the shaft member is cylindrical and has a substantially uniform inner diameter.

References Cited in the file of this patent UNLTED STATES PATENTS 603,244 Avery May 3, 1898 998,587 Mueller July 1-8, 1911 1,217,960 Klorer Mar. 6, 1917 1,748,656 S'aemisch' Feb. 15, 1930 1,762,313 Snow et a1. June 10, 1930 2,101,707 Ewing Dec. 7, 1937 2,112,673, Lewis. N; Mar. 29, 1938 2,179,089 Hauf. Nov. 7, 1939 2,561,710? Pawsat July 24, 1951 2,614,827 Peach etal. -4 Oct. 21, 1952 

